public class Frag {
    public static void main(String[] args) {
        System.out.println(jump(4));
    }

    public static int jump(int n){
        if(n == 1){
            return 1;
        }
        else {
            if (n == 2){
                return 2;
            }
            else {
                return jump(n-1) + jump(n-2);
            }
        }
    }
}
